Peripheral Nerve Surgeries

Carpal Tunnel Release

Carpal tunnel is a very common problem in females in around their late thirties especially after childbirth. The swelling and repeated movements of the hand in household workers make the space under the tunnel narrow causing nerve compression. Most of the time patients seek opinion of orthopaedic surgeons due to pain. Plastic surgeon being the micro-neural surgeon is a better person to manage this problem. The following discussion is intended to give patients a brief idea about the disease and likely course of treatment.

What is carpal tunnel syndrome? (CTS)

People with CTS experience numbness, tingling, or burning sensations over thumb, index, middle, and radial half of the ring fingers. These digits are innervated by medial nerve. Less-commonly patient may have pain in the hands and loss of grip strength. This group of symptoms is called as carpal tunnel syndrome.

Why does it happen?

Median nerve at the level of wrist passes under a thigh fibrous sheath that is additionally holding all the flexor tendons together (responsible for moving the fingers). After their repetitive use especially in abnormal positions the sheath coveting the tendons swells up causing decreased space for the nerve (leading to compression). Additionally any condition associated with accumulation of oedema fluid (like pregnancy, hypothyroidism, obesity, oral contraceptives, diabetes, pre-diabetes (impaired glucose tolerance), and trauma can cause aggravation of this condition) very rarely some other pathology (synovial tumours, synovitis, nerve tumour, lipomas, and vascular malformation ganglion) that reduces space under the tunnel may cause similar problem.

What problems suggest that I have CTS?

Numbness and paraesthesia in the median nerve distribution are the commonest symptoms of carpal tunnel entrapment syndrome. Pain is often present especially in the morning. One should not wait till weakness and atrophy of the thenar muscles occur as it happens if the condition remains untreated.

Are there any tests to confirm the diagnosis?

There is no specific guideline but combination of patient’s symptoms, clinical findings, and electrophysiological testing are assessed to reach the diagnosis. The patient’s complaints have been described above. Clinically a positive Tinel’s sign at the carpal tunnel, an abnormal sensory testing such as two-point discrimination have been standardised as clinical diagnostic criteria by consensus by the panel of experts.

Few other tests like Phalens test, reverse Phalens test, darkens carpal compression test, hand elevation test if positive can support clinical diagnosis. Negativity of these tests doesn’t rule out the diagnosis.

Electro diagnostic testing (electromyography and nerve conduction velocity) can objectively verify the median nerve dysfunction. If these tests are normal, carpal tunnel syndrome is either absent or very, very mild.

Can it be prevented?

Healthy habits such as avoiding repetitive stress, work modification through use of ergonomic equipment (wrist rest, mouse pad), taking proper breaks, using keyboard alternatives (digital pen, voice recognition, and dictation), and employing early treatments such as taking turmeric (anti-inflammatory), omega-3 fatty acids, and B vitamins have been proposed as methods to help prevent carpal tunnel syndrome.

What is the treatment?

Initially conservative treatment like resting the involved hand for a period of 2 weeks in a splint is attempted. Drugs may be used for relieving the pain and inflammation. If symptoms are relieved, patient may continue with lifestyle modifications.

Steroid injections can also be used to alleviate the swelling and pressure on the median nerve.

For more severe cases of carpal tunnel syndrome, open carpal tunnel release surgery or endoscopic carpal tunnel release may be recommended.

What is the prognosis?

Patients respond very well to CT release. Pain, numbness and paraesthesia if present are relieved immediately after the operation, if there are loss of sensations and loss of grip strength (suggestive of long standing pressure) then the waiting period for recovery increases. (as the nerve has to regenerate after the release). Depending upon the age of the patient the recovery can be partial in these types of long standing compression.

Does it recur?

Recurrence of carpal tunnel syndrome after proper surgical release is rare. Reasons for pain after surgery can be scar crossing the wrist (that takes long to heal due to movements).

Injury to some nerve branch usually the palmar cutaneous nerve. These will settle with time. Very rarely an incomplete release of CT may result in persistence of symptoms (needing further release).

How is the surgery done?

Open CT release is a very minor surgery lasting 20 -30 minutes. It is done under local anaesthesia with a 2-2.5 cm long palmar incision. Patients are usually discharged home on the same day and called after a week for follow up. They usually have a small splint for 2 weeks immobilizing only the wrist. The fingers are usually left out of the splint and patient can do minor works with the hand. Oral pain-killers are given at home and sutures are removed after 2 weeks.

Case 1:

A difficult case of carpal tunnel following extensive synovitis

In these peculiar cases we may need larger incisions to get rid of disease completely